T/R module for satellite TT and C ground link

Abstract

Transmit / Receive (T / R) module that provides multiple simultaneous ground to satellite links with rapid pointing and acquisition. The (T / R) module incorporates independent gain and phase control. Left-hand or right-hand circular polarization can be supplied to dual feed antennas. Present invention allows each antenna to be independently polarized. Low-cost componentry is utilized throughout. On-board control of the (T / R) module is obtained using a complex programmable logic device (CPLD) and a micro controller. CPLD provided separate control of four phase shifters, attenuators, channel polarization as well as transmitter on / off control. Telemetry is provided through built-in test (BIT) routine.

Description

PRIORITY CLAIM UNDER 35 U.S.C. §119(e)[0001]This patent application claims the priority benefit of the filing date of provisional application Ser. Nos. 60 / 566,788, 60 / 566,768 and 60 / 566,770, all having been filed in the United States Patent and Trademark Office on Apr. 30, 2004 and now incorporated by reference herein.STATEMENT OF GOVERNMENT INTEREST[0002]The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.BACKGROUND OF THE INVENTION[0003]This invention relates generally to the design of a Transmit and Receive (TR) module, and, more specifically, to such Transmit and Receive modules suitable for a Phase Array Antenna (PAA) which could provide multiple simultaneous ground to satellite links with pointing and acquisition taking seconds. This invention also relates to the field of digital control design where a digital circuit is used to interface with the Antenna Control Computer to c...

AI Technical Summary

Benefits of technology

The present invention provides an apparatus for a multi-beam, Transmit and Receive module that can increase the number of satellite communication links to the Air Force Satellite Control Network, providing more reliable tracking, telemetry, and command. The module can accomplish multiple simultaneous operations, with pointing and acquisition taking seconds. The module includes a six pin RF front connecter, digital phase shifter, digital attenuator, power amplifiers, low noise amplifiers, power combiner, plurality of single pole double throw switches, plurality of five volts DC power switches, and a temperature sensor. The module also includes a polarization circuit that can provide independent left hand and right hand circular polarization to the antenna ports. The apparatus provides a solution for on-board control of Transmit and Receive modules and can programmably control the T / R Module settings and perform built-in tests. The power supplies to the module are routed through power switches that have short circuit and thermal protection features, allowing hot plugging mechanism for the module without turning off the whole system. The module can offer superior performance, operability, adaptability, and maintainability for satellite operation.

Problems solved by technology

The current reflector antennas used to support satellite operations are approximately 10 m in diameter and are susceptible to single point failure and long downtime for repair and maintenance.

Because of the mechanical movement and heavy weight of the reflector antenna, operators cannot quickly schedule consecutive satellite contacts.

Because of these factors, the efficiency of reflector antenna operation is low in terms of throughput and turnaround time.

The mechanical nature of the antenna also limits its flexibility to support new SATOPS requirements and operational concepts.

In addition, the high operational and maintenance cost of a large reflector antenna contributes to its high life-cycle cost despite its lower initial cost.

Other limitations include: cable wrap and keyhole effect.

To date, phased array antennas have not been used for satellite TT&C operations primarily because of their high acquisition cost in comparison to technically inferior, but cheaper conventional reflector antennas.

Low cost component design and implementation issues are critical in developing a practical phased array antenna.

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